Ups is an open source source-level debugger developed in the late 1980s for Unix and Unix-like systems, originally developed at the University of Kent by Mark Russell. It supports C and C++, and Fortran on some platforms. The last beta release was in 2003.
Unlike more popular debugger stacks for modern Unix platforms, ups is completely self-contained — not merely a graphical front-end to lower-level debuggers like gdb. The ups user interface is built directly upon the X Window System and SunView, i.e. it does not use an intermediate widget toolkit such as Motif or GTK+.